Abstract

Previous studies suggest that insulin-sensitizing agents could play a significant role in the treatment of major depression, particularly depression in patients with documented insulin resistance or those who are resistant to standard psychopharmacological approaches. This study aimed to assess the effects on depressive symptoms with adjuvant treatment with the PPARγ-agonist pioglitazone. Patients (N=37) with non-psychotic, non-remitting depression receiving standard psychiatric regimens for depression were randomized across an insulin sensitivity spectrum in a 12-week double blind, randomized controlled trial of pioglitazone or placebo. Improvement in depression was associated with improvement in glucose metabolism but only in patients with insulin resistance. An age effect was also shown in that response to pioglitazone was more beneficial in younger aged patients. Study findings suggest differential improvement in depression severity according to both glucose metabolic status and level of depression at baseline. A greater understanding of the reciprocal links between depression and IR may lead to a dramatic shift in the way in which depression is conceptualized and treated, with a greater focus on treating and/or preventing metabolic dysfunction.

Abstract

The transition to motherhood is a time of elevated risk for clinical depression. Dispositional optimism may be protective against depressive symptoms; however, the arrival of a newborn presents numerous challenges that may be at odds with initially positive expectations, and which may contribute to depressed mood. We have explored the relative contributions of antenatal and postnatal optimism regarding maternity to depressive symptoms in the postnatal period. Ninety-eight pregnant women underwent clinician interview in the third trimester to record psychiatric history, antenatal depressive symptoms, and administer a novel measure of optimism towards maternity. Measures of depressive symptoms, attitudes to maternity, and mother-to-infant bonding were obtained from 97 study completers at monthly intervals through 3 months postpartum. We found a positive effect of antenatal optimism, and a negative effect of postnatal disconfirmation of expectations, on depressive mood postnatally. Postnatal disconfirmation, but not antenatal optimism, was associated with more negative attitudes toward maternity postnatally. Antenatal optimism, but not postnatal disconfirmation, was associated with reduced scores on a mother-to-infant bonding measure. The relationships between antenatal optimism, postnatal disconfirmation of expectations, and postnatal depression held true among primigravidas and multigravidas, as well as among women with prior histories of mood disorders, although antenatal optimism tended to be lower among women with mental health histories. We conclude that cautious antenatal optimism, rather than immoderate optimism or frank pessimism, is the approach that is most protective against postnatal depressive symptoms, and that this is true irrespective of either mood disorder history or parity. Factors predisposing to negative cognitive assessments and impaired mother-to-infant bonding may be substantially different than those associated with depressive symptoms, a finding that merits further study.

Abstract

To examine the occurrence of menstrually-entrained mood cycling in women with treated bipolar disorder as compared to healthy controls, and to explore whether there is a specific effect of lamotrigine in dampening menstrually-entrained cyclicity of mood.Observational comparison study of daily self-ratings of mood, sleep, and insomnia obtained over a mean of four menstrual cycles in 42 women with bipolar disorder taking lamotrigine as part of their treatment, 30 women with bipolar disorder receiving mood stabilizing regimens without lamotrigine, and 13 healthy controls, all with physiological menstrual cycles. Additional exploratory analysis of interactions between psychopharmacological regimen and hormonal contraceptive use in the group of women with bipolar disorder, with the addition of 19 women with bipolar disorder who were using hormonal contraceptives.Women treated for bipolar disorder manifested lower average mood, longer average nightly sleep duration, and greater fluctuations in mood and sleep across menstrual cycle phases than healthy controls. Women with bipolar disorder who were taking lamotrigine had less fluctuation in mood both within and across menstrual cycle phases, and were more similar to the control group than to women with bipolar disorder who were not taking lamotrigine in this respect. In addition, medications with GABA-A receptor modulating effects were found to result in improved mood ratings when combined with hormonal contraceptives.Menstrually-entrained mood fluctuation is present in women treated for bipolar disorder to a greater degree than in healthy controls. Lamotrigine may be of use in mitigating this fluctuation. GABA-A receptor modulators in general may act synergistically with hormonal contraceptives to enhance mood in women with bipolar disorder; this hypothesis merits further study.

Abstract

This study aims to summarize the current state of knowledge regarding approaches to treatment-resistant depression in pregnancy and the postpartum period and to develop algorithms for ante- and postnatal management in cases of refractory major depression. PubMed, Scopus, Google Scholar, and the Cochrane Library databases were searched without temporal restriction. Search terms included pregnancy and depression, perinatal depression, postnatal depression, treatment resistance and depression, antipsychotics and pregnancy, antidepressants and pregnancy, and mood stabilizers and pregnancy. Abstracts were reviewed for relevance, and further articles were obtained from bibliographic citations. There is a significant subpopulation of patients in pregnancy and postpartum whose depressive symptoms do not respond to first-line treatments. No research studies have focused specifically on this population. Data extracted from studies on women with depressive symptoms in pregnancy suggest that in the absence of evidence on which to base clinical decisions, many are receiving combinations of psychotherapeutic medications that have not been specifically studied for use in pregnancy. Antidepressant use in pregnancy is well studied, but studies specifically addressing the case of the patient who does not respond to first-line treatments are absent. Research in this area is urgently needed. The authors review a number of possible therapeutic approaches to treatment-resistant depression in pregnancy and the postpartum period.

Abstract

Precursor proteolysis is a crucial mechanism for regulating protein structure and function. Signal peptidase (SP) is an enzyme with a well defined role in cleaving N-terminal signal sequences but no demonstrated function in the proteolysis of cellular precursor proteins. We provide evidence that SP mediates intraprotein cleavage of IgSF1, a large cellular Ig domain protein that is processed into two separate Ig domain proteins. In addition, our results suggest the involvement of signal peptide peptidase (SPP), an intramembrane protease, which acts on substrates that have been previously cleaved by SP. We show that IgSF1 is processed through sequential proteolysis by SP and SPP. Cleavage is directed by an internal signal sequence and generates two separate Ig domain proteins from a polytopic precursor. Our findings suggest that SP and SPP function are not restricted to N-terminal signal sequence cleavage but also contribute to the processing of cellular transmembrane proteins.

Abstract

We report the case of a 30-year-old woman with severe, prolonged refractory status epilepticus requiring more than 6 months of iatrogenic coma. Opinions on prognosis and clinical management were solicited from a number of experienced neurointensivists and epileptologists at multiple time-points during the clinical course. The ensuing discussion, annotated with references, is presented here. Several experts commented on isolated cases of young patients with encephalitis requiring up to 2-3 months of iatrogenic coma, yet still having good outcomes. Treatments discussed include ketamine, gammaglobulin, plasmapheresis, steroids, adrenocorticotropic hormone, very high-dose phenobarbital, isoflurane, lidocaine, electroconvulsive therapy, ketogenic diet, hypothermia, magnesium, transcranial magnetic stimulation, vagus nerve stimulation, deep brain stimulation, and neurosurgery. The patient eventually suffered a cardiac arrest but was resuscitated as requested by the family. Seizures then stopped, and the patient has remained in a persistent vegetative state since.

Abstract

The contribution of arachidonic acid (AA) release and metabolism to the toxicity that results from glutathione (GSH) depletion was studied in rat mesencephalic cultures treated with the GSH synthesis inhibitor l-buthionine sulfoximine. Our data show that GSH depletion is accompanied by increased release of AA, which is phosholipase A2 (PLA2) dependent. Exogenous AA is toxic to GSH-depleted cells. This toxicity is prevented by inhibition of lipoxygenase activity, suggesting participation of toxic byproducts of AA metabolism. Hydroxyperoxyeicosatetraenoic acid (HPETE), one of the primary products of AA metabolism by lipoxygenase is also toxic to GSH-depleted cells, whereas hydroeicosatetraenoic acid (HETE) is not. Cell death caused by GSH depletion is prevented by: (i) replenishment of GSH levels with GSH-ethyl ester; (ii) inhibition of PLA2 activity; (iii) inhibition of lipoxygenase activity; and (iv), treatment with ascorbic acid. These data suggest that the following events likely contribute to cell death when GSH levels become depleted. Loss of GSH results in increased release of AA, which is PLA2 dependent. Metabolism of arachidonic acid via the lipoxygenase pathway results in generation of oxygen free radicals possibly produced during conversion of HPETE to HETE, which contribute to cellular damage and death. Our study suggests that limiting AA release and metabolism may provide benefit in conditions with an existing depletion of GSH, such as Parkinson's disease.

Abstract

Glutathione is an important cellular antioxidant present at high concentrations in the brain. We have previously demonstrated that depletion of glutathione in mesencephalic cultures results in cell death and that the presence of glia is necessary for the expression of toxicity. Cell death following glutathione depletion can be prevented by inhibition of lipoxygenase activity, implicating arachidonic acid metabolism in the toxic events. In this study we examined the effect of glial activation, known to cause secretion of cytokines and release of arachidonic acid, on the toxicity induced by glutathione depletion. Our data show that treatment with the endotoxin lipopolysaccharide activated glial cells in mesencephalic cultures, increased interleukin-1beta in microglia and caused depletion of glutathione. The overall effect of lipopolysaccharide treatment, however, was protection from damage caused by glutathione depletion. Addition of cytokines or growth factors, normally secreted by activated glia, did not modify L-buthionine sulfoximine toxicity, although basic fibroblast growth factor provided some protection. A large increase in the protein content and the activity of Mn-superoxide dismutase, observed after lipopolysaccharide treatment, may indicate a role for this mitochondrial antioxidant enzyme in the protective effect of lipopolysaccharide. This was supported by the suppression of toxicity by exogenous superoxide dismutase. Our data suggest that superoxide contributes to the damage caused by glutathione depletion and that up-regulation of superoxide dismutase may offer protection in neurodegenerative diseases associated with glutathione depletion and oxidative stress.